I'm trying to create following network scheme:

[wire clients]--wrt54g[1]-
                           
[wire clients]--wrt54g[2]--->wireless-->wrt54g[0]--LAN
                           /
[wire clients]--wrt54g[3]-/

wrt54g[0] should route and 1-3 should bridge their lan-wifi interfaces.
(thus there would be one hop going from wire client to LAN)

So far I've encountered number of problems:

1. I couldn't get wrt54g working when mode is STA and eth1 belongs to bridge: ifconfig shows no packets are received.
If mode is changed to WET it seems to start working, but very unreliably (many packet losses). I can bridge when in AP mode (this is default) fine.

2. I couldn't get WPA working on wrt54g acting as client. I've tried both,
-A and -S modes.

I've found in http://www.seattlewireless.net/index.cgi/LinksysWrt54g
about wl_sta.o module, which should be used if wrt54g is in client mode: but couldn't find that file in any linksys source package.

Then I've tried using WDS, better luck here, wds works ok in bridge and I can bridge eth1 "alone", thus getting router instead of bridge.
Performance is almost twice as bad (using only 2 devices), STA-to-AP would get me ~2.7MB/s, wds only ~1.5MB/s.

Next problem is reconnection: after simulating one device power failure, link usually doesn't get reestablished until second device is rebooted: I've solved it using custom script to "wl reboot" if partner can't be reached, but it's not long term solution.

Please post any ideas and comments.

Bridge + Client mode is a pain.
Don't use it.

Separate LAN + WLAN on your WRTs (client mode + AP).

So you need to brick the bridge br0 on 4 WRTs in your case.

Read this, how it works:

http://openwrt.org/forum/viewtopic.php? … wto+client

Thanks.
That went ok, small subnets (255.255.255.240) on end wrts even make sense.

However I'm still "having" problems with reconnection after power failure:
If AP is powered down and plugged in again after several seconds, client reconnects ok.
If client is powered down/up, it never connects to AP: wl down/wl up, wl joint <ssid> etc. doesn't help.
wl scan finds AP, iwconfig shows correct AP mac and ssid but no data is transfered.
If AP is rebooted client reconnects right away.

I could (and am) using simple script to reboot (or more exactly, wl down/up) AP when it can't reach client, but that won't be pretty with several clients.

Update:

Reconnection problems seems to be related to WEP. Disable it and both units reconnect just fine.

Also it doesn't seems to be only problem with reconnection, wifi nic "crashes" after ~1GB data is send, seems to work ok (so far) with WEP disabled.

I'm using 128bit key, haven't tried shorter ones yet.

With wep disabled got units running/transfering for about two days - no problems whatsoever.

Using different (40, 64 bit) WEP keys doesn't seems to help.

Anyone can confirm this?

I'm still looking for wl_sta.o module, no luck so far.

Dunno, i use the one WRT in client mode for internet browsing with one wired PC attached to it.
I hadn't any problems so far.

I just have set wl0_mode to sta and it works.
Even with WEP 128 on both sites

But to be true, I don't access the WRT client from the intranet site, so I can't really tell you if it looses the connection from time to time.

I know Sveasoft has written for Alchemy some monitoring application which probhits that behavior.
Maybe you can port it ?